Voidgamers Home| I had stumbled upon Vatican Art Stone material by accident and found it to be far superior to any of the plasters I had every used. With that said, now I will put my money where my mouth is: 1 - I use 8oz styrofoam cups to mix my material in. Depending on the mold, I will use just a tad more water and material if their are a large number of thick pieces (like the wizard's tower). 2 - I use about 1.5 - 2.0 oz (1/4 of the cup) with water. I then use an other cup to scoop the VAS out of the bag and pour it into the cup of water. I slowly siftingly pour in small amounts trying not to lump any of it together as it pours. I do not mix while pouring, I wait for the VAS to absorb and sink into the water then continue pouring. When the pile under the water gets to just about to the top of the water. (note: the water is also being displaced by the VAS, so the water level will rise as a result.) The mix I use remains more watery than the 'standard' with plaster. 3 - Once the 'proper' Mk1 eyeball measurement is completed, I mix the material with the handle of an old paintbrush making sure the mixture has no clumps in the sides or the middle at the bottom. The consistancy should be like milk, but the bubbles should not keep spinning around the edges when you stop mixing. 4 - I then pour the mix one cavity at a time. The parts fill pretty easy and the first few will be a little more watery than the rest of the mix. The very first things you should cast with the watery mix is the parts with the fine detail or a large 'lip' of an undercut. Parts with big detail would be those in the Tomb mold and one with a large undercut would be the step pieces in the prison tower. Between each pour, I mix the material a little to make sure the water and VAS have an equal part in the remainder of the cup. I pour slowly to be sure not to overfill the cavity (which wastes material) then move on to the next cavity after stirring a little more. If the mix get's to thick, the air-bubbles will get trapped under the material and voids will form. 5 - I tap the sides of the molds with my scraper to get the air bubbles out and to fill the remainder of the cavity with material. Sometimes the material will splash out if I hit the mold to hard. Scraping will normally fill these cavities back in with material. 6 - I scrape the layer of material on the top of the mold towards opposite corners from the most filled to the least filled (thus filling in any cavities that did not have anough material in it.) I will usually scrape immediately after casting. The cavities are so full of heavy material that the scraping does not make any difference in the timing. However, you wait to long and the material hardens to the point that you will deform the blocks. The silicone is not strong enough (by design) to hold up against a stern scraping. It may remain plyable, but it will not remain 'straight' in the cavity. Scraping immediately after casting makes the process so much easier. 7 - Demold: I usually wait about a half hour for the casting to dry, although if I am waiting for a piece to continue a project, I will sometimes pull the part earlier than that time if it seems ready. I have found that the parts will need an other hour or so to dry before they actually feel dry. Since I use Elmer's glue to fasten all of the parts together, the wetness in the stone will prolong the glue curing time - not good when you are trying to accomplish a critical step in a project. I have found that placing newly cast blocks ontop of very dry blocks (blocks that are days or more old), the drying time is shortened even further. The dry blocks seem to absorb the water in the blocks above them or they help evaporation or something. I'm not certain which - it just works. This was not the case for the dental plasters I have used. I have made many new pieces in a crazy attempt to 'create' as fast as possible. I have tried casting with more water & material to get more than one mold cast at a time. The attempts almost always end in failure. The second mold always suffers from to-thick-material trying to push into the cavities rather than pouring out nicely. So I stick with the 2oz eyeball mix and then pour more water into the empty cup even though there is still some material in it. I repeat the process several times for each mold, while trying to pay attention to the already cast molds to be sure to scrape again if necessary. I use a plastic tray table for my casting platform. It is mobile, plastic, and easy to clean. I had used alamunium foil under the molds, which works like a charm to remove the excess scraped material, but it crinkles and will sometimes lift the molds off of the flat surface, thus creating whacky shaped blocks. So I keep to the plastic and scrape off or twist off the excess between castings. I also use a 4" wide plastic scraper. I want to be sure to cover the entire mold in each pass and not have to worry about getting the scraper to cover the mold precisely. I also use a smaller scraper for the small jobs or when there are to many molds on the tray for the large scraper to fit between. Scott
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